@import url('https://fonts.googleapis.com/css2?family=Orbitron:wght@400;700;900&family=Share+Tech+Mono&display=swap');

* { margin: 0; padding: 0; box-sizing: border-box; }

:root {
    --c0: #ff2d78;
    --c1: #00ff88;
    --c2: #ffcc00;
    --c3: #00cfff;
    --bg: #00000c;
    --hud-h: 64px;
}

body {
    background: var(--bg);
    color: #fff;
    font-family: 'Orbitron', 'Courier New', monospace;
    overflow: hidden;
    width: 100vw;
    height: 100vh;
    user-select: none;
}

/* ── SCREENS ── */
#game-container { position: relative; width: 100%; height: 100%; }

.screen {
    position: absolute; inset: 0;
    display: none;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}
.screen.active { display: flex; }

/* ── MENU ── */
#menu-screen {
    background: radial-gradient(ellipse at 50% 30%, #260030 0%, #00000c 65%);
    gap: 2rem;
}

#logo {
    font-size: clamp(3rem, 8vw, 6rem);
    font-weight: 900;
    letter-spacing: 0.05em;
    text-shadow: 0 0 40px var(--c0), 0 0 80px var(--c0);
    animation: pulse-glow 2s ease-in-out infinite alternate;
}
#logo span { color: var(--c0); }

@keyframes pulse-glow {
    from { text-shadow: 0 0 30px var(--c0), 0 0 60px var(--c0); }
    to   { text-shadow: 0 0 50px var(--c0), 0 0 100px var(--c0), 0 0 150px #ff007b55; }
}

.tagline {
    text-align: center;
    font-size: 1rem;
    color: var(--c2);
    text-shadow: 0 0 12px var(--c2);
    letter-spacing: 0.3em;
    margin-top: -0.5rem;
}

.section-label {
    font-size: 0.75rem;
    letter-spacing: 0.3em;
    color: #555;
    text-align: center;
    margin-bottom: 0.75rem;
}

#song-list { display: flex; flex-direction: column; gap: 0.5rem; width: min(420px, 90vw); }

.song-btn {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: rgba(0,212,255,0.02);
    border: 1px solid rgba(0,212,255,0.2);
    color: #fff;
    font-family: inherit;
    font-size: 0.9rem;
    padding: 0.7rem 1.2rem;
    cursor: pointer;
    letter-spacing: 0.08em;
    transition: background 0.15s, border-color 0.15s, box-shadow 0.15s, transform 0.1s;
    width: 100%;
    text-align: left;
}
.song-btn:hover {
    background: rgba(0,212,255,0.08);
    border-color: #00d4ff;
    box-shadow: 0 0 18px rgba(0,212,255,0.35);
    transform: translateX(4px);
}
.song-btn .diff {
    font-size: 0.65rem;
    letter-spacing: 0.12em;
    padding: 2px 6px;
    border: 1px solid currentColor;
}
.diff-easy   { color: var(--c1); }
.diff-medium { color: var(--c2); }
.diff-hard   { color: var(--c0); }
.diff-expert { color: #cc44ff; }

#key-legend {
    display: flex;
    gap: 1.5rem;
    font-size: 0.75rem;
}
.key-item { display: flex; gap: 0.3rem; align-items: center; }
.key-box {
    border: 1px solid currentColor;
    padding: 3px 7px;
    font-size: 0.7rem;
    opacity: 0.8;
}
.lane-color-0 { color: var(--c0); }
.lane-color-1 { color: var(--c1); }
.lane-color-2 { color: var(--c2); }
.lane-color-3 { color: var(--c3); }

/* ── COUNTDOWN ── */
#countdown-screen {
    background: #00000c;
    gap: 1rem;
}
#countdown-song-name {
    font-size: 1.4rem;
    letter-spacing: 0.2em;
    color: #aaa;
}
#countdown-number {
    font-size: 8rem;
    font-weight: 900;
    color: var(--c0);
    text-shadow: 0 0 60px var(--c0);
    animation: cd-pop 0.4s ease-out;
}
@keyframes cd-pop {
    0%   { transform: scale(1.5); opacity: 0; }
    100% { transform: scale(1);   opacity: 1; }
}

/* ── GAME SCREEN ── */
#game-screen {
    background: var(--bg);
    justify-content: flex-start;
}

/* HUD */
#hud {
    width: 100%;
    height: var(--hud-h);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 1.5rem;
    background: rgba(0,0,0,0.6);
    border-bottom: 1px solid #ffffff0a;
    flex-shrink: 0;
}
.hud-block { display: flex; flex-direction: column; align-items: flex-start; min-width: 100px; }
.hud-block.center { align-items: center; flex: 1; }
.hud-block.right { align-items: flex-end; }
.hud-label { font-size: 0.55rem; letter-spacing: 0.2em; color: #555; }

#score {
    font-size: 1.6rem;
    font-weight: 700;
    color: #00d4ff;
    text-shadow: 0 0 10px #00d4ff;
}
#song-title-hud {
    font-size: 0.8rem;
    letter-spacing: 0.15em;
    color: #888;
    margin-bottom: 0.3rem;
}
#combo {
    font-size: 1.4rem;
    font-weight: 700;
    color: #00d4ff;
    text-shadow: 0 0 10px #00d4ff;
}
#multiplier {
    font-size: 0.7rem;
    color: #ff8c00;
    letter-spacing: 0.1em;
}

/* Health bar */
#health-bar-wrap {
    width: 200px;
    height: 6px;
    background: #1a1a2a;
    border-radius: 3px;
    overflow: hidden;
}
#health-bar {
    height: 100%;
    width: 100%;
    background: linear-gradient(90deg, var(--c0), var(--c2));
    border-radius: 3px;
    transition: width 0.15s, background 0.3s;
}

/* GAME AREA */
#game-area {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: stretch;
    position: relative;
    overflow: hidden;
}

/* Scrolling grid background */
#game-area::before {
    content: '';
    position: absolute; inset: 0;
    background:
        repeating-linear-gradient(0deg, transparent, transparent 49px, rgba(255,255,255,0.025) 50px),
        repeating-linear-gradient(90deg, transparent, transparent 119px, rgba(255,255,255,0.015) 120px);
    animation: scroll-grid 1.2s linear infinite;
    pointer-events: none;
    z-index: 0;
}
@keyframes scroll-grid {
    from { background-position: 0 0, 0 0; }
    to   { background-position: 0 50px, 0 0; }
}

/* LANES */
#lanes {
    display: flex;
    gap: 3px;
    height: 100%;
    padding: 0 4vw;
    position: relative;
    z-index: 1;
}

.lane {
    width: 110px;
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.lane-bg {
    position: absolute; inset: 0;
    background: rgba(255,255,255,0.012);
    border-left: 1px solid rgba(255,255,255,0.04);
    border-right: 1px solid rgba(255,255,255,0.04);
}

/* Lane accent colors via nth-child */
.lane:nth-child(1) { --lc: var(--c0); }
.lane:nth-child(2) { --lc: var(--c1); }
.lane:nth-child(3) { --lc: var(--c2); }
.lane:nth-child(4) { --lc: var(--c3); }

.key-hint {
    position: absolute;
    top: 10px;
    font-size: 0.6rem;
    color: var(--lc);
    opacity: 0.7;
    letter-spacing: 0.05em;
    text-shadow: 0 0 6px var(--lc);
    z-index: 3;
}

/* Hit zone */
.hit-zone {
    position: absolute;
    bottom: 36px;
    width: 72px;
    height: 72px;
    border-radius: 50%;
    border: 3px solid var(--lc);
    box-shadow: 0 0 12px var(--lc), inset 0 0 12px rgba(0,0,0,0.5);
    background: rgba(0,0,0,0.4);
    transition: background 0.05s, box-shadow 0.05s, transform 0.05s;
    z-index: 3;
}
.hit-zone.pressed {
    background: var(--lc);
    box-shadow: 0 0 40px var(--lc), 0 0 80px var(--lc)55;
    transform: scale(1.08);
}

/* Divider line above hit zone */
.lane::after {
    content: '';
    position: absolute;
    bottom: 110px;
    left: 0; right: 0;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--lc), transparent);
    opacity: 0.3;
    z-index: 2;
}

/* NOTES */
.note {
    position: absolute;
    width: 72px;
    height: 22px;
    border-radius: 6px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--lc);
    box-shadow: 0 0 10px var(--lc), 0 0 22px var(--lc)88;
    border: 2px solid rgba(255,255,255,0.4);
    z-index: 4;
    will-change: top;
}
.note::after {
    content: '';
    position: absolute;
    inset: 3px 6px;
    background: rgba(255,255,255,0.25);
    border-radius: 3px;
}

/* FEEDBACK */
#feedback-overlay {
    position: absolute;
    top: 40%;
    left: 50%;
    transform: translate(-50%, -50%);
    pointer-events: none;
    z-index: 20;
    font-size: 2rem;
    font-weight: 900;
    text-align: center;
}
.feedback-text {
    display: block;
    animation: fb-rise 0.55s ease-out forwards;
    letter-spacing: 0.08em;
    text-shadow: 0 0 20px currentColor;
}
.fb-perfect { color: var(--c2); }
.fb-good    { color: var(--c1); }
.fb-ok      { color: #88ccff; }
.fb-miss    { color: #ff4444; }

@keyframes fb-rise {
    0%   { opacity: 1; transform: translateY(0)   scale(1.2); }
    80%  { opacity: 0.7; }
    100% { opacity: 0; transform: translateY(-50px) scale(0.9); }
}

/* HIT PARTICLES */
.particle {
    position: absolute;
    border-radius: 50%;
    pointer-events: none;
    animation: particle-fly 0.7s ease-out forwards;
    z-index: 10;
}
@keyframes particle-fly {
    0%   { opacity: 1; transform: translate(0, 0) scale(1); }
    100% { opacity: 0; transform: translate(var(--tx), var(--ty)) scale(0); }
}

/* RESULTS SCREEN */
#results-screen {
    background: radial-gradient(ellipse at 50% 20%, #1e0028 0%, #00000c 70%);
    gap: 1.2rem;
}
#result-heading {
    font-size: clamp(1.5rem, 4vw, 2.5rem);
    letter-spacing: 0.2em;
    color: var(--c0);
    text-shadow: 0 0 20px var(--c0);
}
#rank-box {
    font-size: 5rem;
    font-weight: 900;
    line-height: 1;
}
#rank-letter { text-shadow: 0 0 30px currentColor; }
.rank-S { color: var(--c2); }
.rank-A { color: var(--c1); }
.rank-B { color: var(--c3); }
.rank-C { color: #ff8c00; }
.rank-D { color: #ff4444; }

#result-stats {
    display: flex; flex-direction: column;
    gap: 0.4rem;
    width: min(340px, 85vw);
}
.stat-row {
    display: flex;
    justify-content: space-between;
    padding: 0.45rem 1rem;
    border-bottom: 1px solid #1a1a2a;
    font-size: 0.95rem;
}
.stat-label { font-size: 0.65rem; color: #555; letter-spacing: 0.15em; align-self: center; }
.perfect-color span { color: var(--c2); }
.good-color    span { color: var(--c1); }
.miss-color    span { color: #ff4444; }

#result-btns { display: flex; gap: 1rem; margin-top: 0.5rem; }

.menu-btn {
    background: linear-gradient(135deg, rgba(0,212,255,0.1), rgba(147,51,234,0.1));
    border: 1px solid rgba(0,212,255,0.4);
    color: #fff;
    font-family: inherit;
    font-size: 0.85rem;
    letter-spacing: 0.15em;
    padding: 0.65rem 2rem;
    cursor: pointer;
    transition: background 0.15s, box-shadow 0.15s, border-color 0.15s;
}
.menu-btn:hover {
    background: linear-gradient(135deg, rgba(0,212,255,0.2), rgba(147,51,234,0.2));
    border-color: #00d4ff;
    box-shadow: 0 0 20px rgba(0,212,255,0.3), 0 0 40px rgba(147,51,234,0.15);
}

/* ── MOBILE TOUCH CONTROLS ── */
#mobile-controls {
    display: none;
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    height: 110px;
    z-index: 9000;
    gap: 3px;
    padding: 0 2px 6px;
}

.touch-zone {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 8px 8px 0 0;
    font-family: 'Orbitron', monospace;
    font-weight: 900;
    font-size: 1.4rem;
    letter-spacing: 0.05em;
    user-select: none;
    -webkit-user-select: none;
    touch-action: manipulation;
    transition: background 0.08s, box-shadow 0.08s;
}
.touch-zone:nth-child(1) { background: rgba(255,45,120,0.2); border: 2px solid var(--c0); color: var(--c0); }
.touch-zone:nth-child(2) { background: rgba(0,255,136,0.2);  border: 2px solid var(--c1); color: var(--c1); }
.touch-zone:nth-child(3) { background: rgba(255,204,0,0.2);  border: 2px solid var(--c2); color: var(--c2); }
.touch-zone:nth-child(4) { background: rgba(0,207,255,0.2);  border: 2px solid var(--c3); color: var(--c3); }

.touch-zone.active:nth-child(1) { background: rgba(255,45,120,0.55);  box-shadow: 0 0 30px var(--c0); }
.touch-zone.active:nth-child(2) { background: rgba(0,255,136,0.55);   box-shadow: 0 0 30px var(--c1); }
.touch-zone.active:nth-child(3) { background: rgba(255,204,0,0.55);   box-shadow: 0 0 30px var(--c2); }
.touch-zone.active:nth-child(4) { background: rgba(0,207,255,0.55);   box-shadow: 0 0 30px var(--c3); }

@media (hover: none) and (pointer: coarse) {
    #mobile-controls { display: flex; }
    #game-area { padding-bottom: 110px; }
    .key-hint { display: none; }
    .lane { width: 25vw; }
    #lanes { padding: 0; }
}

/* ── RESPONSIVE CANVAS ── */
@media (max-width: 600px) {
    #hud { padding: 0 0.5rem; }
    .hud-block { min-width: 60px; }
    #score { font-size: 1.1rem; }
    #combo { font-size: 1rem; }
    #health-bar-wrap { width: 100px; }
    .hit-zone { width: 52px; height: 52px; bottom: 24px; }
    .note { width: 52px; height: 18px; }
    .lane::after { bottom: 80px; }
}

/* ── SPACE THEME: Nebula Blobs ── */
.nebula-blob {
    position: fixed;
    border-radius: 50%;
    pointer-events: none;
    filter: blur(80px);
    opacity: 0.15;
    z-index: 0;
    animation: nebulaFloat 20s ease-in-out infinite alternate;
}
.nebula-blob.nb1 {
    width: 500px; height: 500px;
    background: radial-gradient(circle, #00d4ff 0%, transparent 70%);
    top: -10%; left: -5%;
}
.nebula-blob.nb2 {
    width: 400px; height: 400px;
    background: radial-gradient(circle, #9333ea 0%, transparent 70%);
    bottom: -10%; right: -5%;
    animation-delay: -10s;
}
@keyframes nebulaFloat {
    0%   { transform: translate(0, 0) scale(1); }
    50%  { transform: translate(30px, -20px) scale(1.1); }
    100% { transform: translate(-20px, 15px) scale(0.95); }
}

/* ── SPACE THEME: Scanlines ── */
.scanlines-overlay {
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    pointer-events: none;
    z-index: 9998;
    background: repeating-linear-gradient(
        0deg,
        transparent,
        transparent 2px,
        rgba(0, 212, 255, 0.008) 2px,
        rgba(0, 212, 255, 0.008) 4px
    );
    opacity: 0.5;
}

/* ── SPACE THEME: Starfield Canvas ── */
#starfield-canvas {
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    pointer-events: none;
    z-index: 0;
}